改性海泡石和γ-Al2O3负载Ni-B-Mo合金催化糠醛液相加氢制糠醇

Ni-B-Mo Amorphous Alloy Catalyst Loaded on Modified Sepiolite and γ-Al_2O_3 for Liquid Phase Hydrogenation of Furfural to Furfuryl Alcohol

分别以改性海泡石(Sep)和γ-Al2O3为载体,采用浸渍还原法制备了负载型Ni-B-Mo合金催化剂,用于催化糠醛液相加氢。研究发现,Ni-B-Mo/Sep催化剂上糠醛转化率为83.8%、糠醇的选择性为98.7%,均优于Ni-B-Mo/γ-Al2O3。采用差热分析(DTA)、NH3吸附红外光谱(IR)、比表面积测试(BET)和程序升温脱附(TPD)等技术,考察了载体对Ni-B-Mo合金催化剂性能的影响。研究结果表明,Ni-B-Mo/Sep表现出高活性主要是由于其独特的合金组成、较高的Ni含量和L酸中心、对反应物中等强度的吸附中心变弱以及吸附中心数目增多、具有更少的吸附产物中心所致。Ni-B-Mo/Sep选择性更高主要是由于其对糠醇吸附的强度较弱,不易发生深度加氢。

Ni-B-Mo/Sep and Ni-B-Mo/T-Al2O3 amorphous alloy catalyst were prepared by impregnation combined with chemical reduction method, and were used for catalyzing liquid phase hydrogenation of furfural （FFR） to furfuryl alcohol （FFA）. Compared with Ni-B-Mo/T-A1203, Ni-B-Mo/Sep exhibits higher activity and selectivity;the conversion of furfural and selectivity to furfuryl alcohol is 83.8% and 98.7% ,respectively. Effects of carriers on the the properties of the catalyst were investigated by differential thermal analysis, NH3-adsorption infrared spectra, BET surface area and temperature programmed desorption of hydrogen, furfural and furfuryl alcohol. The higher activity of Ni-B-Mo/Sep is attributed to the unique structure of amorphous alloy, more loading of Ni and Lewis acid center, more number of middle-strong adsorption center of H2 and FFR, and less adsorption center of FFA. The superior selectivity to furfury alcohol is mainly due to the weaker adsorption of FFA on the surface of Ni-B-Mo/Sep, resulting in less chance for further hydrogenation of FFA.